EP1265662B1 - Device for administering liquids - Google Patents

Abstract

A device for dispensing liquid from a bag has upper and lower casing halves and a closure holding together the casing halves. A pressure piston in the casing can press the bag against the lower casing half. This piston is operated by a rocking lever having an upper end bearing on the upper casing half and a lower end on which the piston is pivoted and a tension spring and flexible element connected between the casing halves and the upper end of the rocking lever and angularly biasing the lever for movement from a generally horizontal position with the piston raised and a tilted position with the piston lowered for applying such a force to the pressure piston that a pressure is generated in the bag that causes the discharge of a constant liquid volume per unit of time.

Description

The present invention relates to a device for Administration of fluids, in particular infusion solutions.

Such devices are known. An application such a device relates, for example, the Administration of an infusion solution over a long period of time, wherein the infusion solution in relatively small amounts over the appropriate period of time to be administered. Such a device is also called "infusion pump" designated. It ensures that the example in an infusion bag contained infusion fluid the infusion bag via a tube system the body of the Patient is supplied.

From DE 295 08 249 U1 is a device for administering of medical fluids with one with the too administering fluid-filled bellows-shaped container known. This bellows-type container is in one used in a substantially cylindrical housing, with a cap-like, the housing wall cross-lid is closed. In the housing cover is a the bellows container with a compressive force acting on Spring. Cover and housing wall act over one Thread together so that with increasing unscrewing the Lids on the housing of the bellows-like container increasingly is pressurized and thereby the in it contained to be administered liquid.

A disadvantage of this known device that with increasing emptying of the bellows-like container Lid must be screwed on. The administration process therefore does not expire automatically.

From GB-A-2054 381 a device according to the preamble of claim 1 is known.

The present invention is based on the object, a To provide a device for administering fluids which are convenient and self-acting easy to handle or apply and a uniform Dosage of the liquid to be administered allows.

This object is achieved by a device solved according to claim 1.

The solution according to the invention provides a housing that has a lower and an upper housing half, which pivotally or are rotatably connected to each other. A closure holds both housing halves together in the closed state. To insert a liquid (infusion solution) the bag is openable, after which the upper housing half can be opened. After pickled Pouch will be the upper half of the case in the closed State swung back, after which the shutter both Housing halves locked together. The inside of the Housing arranged plunger exercises in the closed state of the housing exerts a force on the filled bag, the delivery of the liquid from the bag, for example via a hose system connected to the bag, ensures. So that the plunger one such Being able to muster up strength, he becomes himself through a mechanism applied to the pressure application, in such a way that a pressure is generated in the bag, the delivery of a constant liquid volume per unit time over the Period of the administration process causes. With others Words, the flow rate of the fluid through a hose connected to the bag is passed over the Administration process kept constant.

The idea according to the invention, instead of a simple one Compression spring system for applying a to be administered Liquid containing bag such Using mechanism is one of the key points of the invention. This mechanism turns on the following Phenomenon out. When the bag is full, i. when the power to to produce a certain pressure does not have to be that big a spring is just the strongest tensioned. When empty Pouch, on the other hand, when the force to a certain pressure To produce very high, the spring is almost not curious; excited. According to the invention it is ensured that despite this feathering the delivery of a constant Liquid volume per unit time is achieved.

The mechanism has one the pressure stamp with a force acting through a tension spring in its angular position relative to the plunger changeable lever on. The force application on The plunger is thus made by changing the Angular position of a lever when the bag is empty is arranged almost perpendicular to the printing stamp plane, while he is in a position when the bag is completely filled occupies almost parallel to the platen plane. With increasing Emptying the bag decreases the angle that the lever with the pressure stamp plane forms, too. This will a uniform pressure build-up in the bag during the administration time ensured.

Specifically, the mechanism preferably has one one end rotatably and slidably on the upper half of the housing stored and at the other end the printing stamp rotatably mounted rocker arm and one at the one end of the Rocker arm via a flexible cable attacking tension spring, the rocker arm in the lowest pressure platen position pretensions corresponding tilting position. If no bag in the housing is inserted, the plunger takes its lowest position, the highest tilted position corresponds to the rocker arm. Is a bag inserted and The housing is closed, the rocker arm in a nearly pivoted to Druckstempelebene parallel position, in the the tension spring is extended to the furthest. With progressing Emptying the bag, the tension spring is increasing relaxed and the tilted position of the lever changed. At the same time thereby the lever arm (distance between Spring attack point and punch pivot on the rocker arm) changed, with the tension spring the force on the plunger transfers. When the bag is full (position of the rocker arm approximately parallel to the plunger) the lever arm is very short, while with empty bag (position of the rocker arm strong inclined) the lever arm is very long. By changing the Leverage is thus the different spring force compensated.

Preferably, the flexible rope is above the top of the Tilt lever guided and the top in a predetermined Contour, in particular approximately roof-shaped, formed, wherein the rope, depending on the angular position of the rocker arm, different is strongly diverted. With this measure will the objective of the invention even better achieved since the rocker arm acts as an eccentric whose contour the Determines leverage ratios. The flexible rope runs here over the contour on the top of the rocker arm, so that the lever arm through the respective contact point of the rope with the contour (preferably roof shape) is determined.

The tension spring is on the inside of the upper half of the housing anchored. It goes without saying that the anchoring point the tension spring with respect to the one rocker arm end, on which the tension spring is attached, beyond the other Tilting lever end (rotatable connection with the draw punch) lies.

Depending on the application, spring characteristics, lever ratio, Lever shape, etc. empirically to determine the appropriate To obtain balance of power.

To create about symmetrical conditions, the Device preferably at least two opposite mutually acting rocker arms with associated opposite acting tension springs, the rocker arms on their respective other ends a common axis of rotation on Own pressure stamp. In development of this embodiment the device has two internal, in one Directional rocker arms and two outboard, in the opposite direction acting rocker arm with corresponding Tension springs on.

The rocker arms are expediently by means of rollers Webs displaceable, the rollers in their final position in complementary concave recesses of the upper half of the housing are rotatably mounted. In this case, each rocker arm preferably on each side of a roll. The roles have in their periphery preferably a groove into which the corresponding guide bar for the storage of the role intervenes. In this way, the role on the bridge unroll, and the rocker arm is against axial movement secured the roles.

The associated tension spring engages on the flexible rope on on the upper end of the rocker arm. The rope is in the upper end area fixed to the rocker arm, for example via a Thickening at the end of the rope taken in there. The tension spring exercises thus over the rope a torque on the rocker arm, to bring this in the almost vertical tilt position. This movement causes a lowering of the plunger and thus compressing the bag (infusion bag).

The housing of the device according to the invention is preferably flat, with one embodiment particularly is preferred, in which the housing and the plunger are formed approximately rectangular.

The inventively designed device can be at appropriate training, as proposed above, comfortable to wear on the body, especially with the help of a belt under a sweater, etc. The housing therefore preferably has At least one belt strap on the back on, through which a belt or belt can be pulled. Due to the flat and especially rectangular shape results a high wearing comfort.

The closure is suitably designed so that he at least one arranged on a housing half, the other Case half when closing outside cross-over and with the other half of the housing in locking engagement passing locking tab having. Preferably, one is on each side Shutter tab provided.

A preferred embodiment is characterized that the device without the aid of special tools not openable. This is to prevent that unwanted manipulations of laymen, for example from Patients themselves, can be performed. The closure is therefore designed so that an opening of the housing with the fingers is not possible.

Rather, a special device is for Closing and opening the device of the above-described Kind of seen before. This device has a lower one stationary bearing part for fixing the device and a manually manageable, bow-shaped upper part, the is pivotally connected to the lower bearing part and a section for pressing against the upper half of the housing the device has. The device for closing and opening (Charger) works by opening the empty device is inserted into the device. The filled bag is inserted into the lower half of the device. With the bow-shaped upper part, the upper half of the housing the device with a reasonable effort pressed against the lower half of the housing until the shutter locks. The device is then ready for operation.

To open the device, the charger preferably at the top of a device for releasing the locking the at least one locking tab with the other housing part on. The means for releasing preferably has a closure flap outwardly moving wedge-shaped Part that can be manually moved down to the Release tab (the closure tabs) to solve. The upper Housing half then snaps up, so that the device then it is open. It can be removed from the charger and be re-loaded with a new filled bag.

Figur 1

eine räumliche Ansicht einer Vorrichtung zur Verabreichung von Flüssigkeiten im geöffneten Zustand, wobei die Federn, Zugseile und Lagereinrichtungen für die Kipphebel im von der oberen Gehäusehälfte gelösten Zustand dargestellt sind;

Figuren 2a-f

schematische Schnittansichten der Vorrichtung der Figur 1, die die Funktionsweise des Mechanismus zur Druckaufbringung in einer stufenweise Abfolge zeigen; und

Figur 3

eine räumliche Darstellung eines Ladegerätes zum Schließen und Öffnen der in den Figuren 1 und 2 gezeigten Vorrichtung.

The invention will now be explained in detail with reference to an embodiment in conjunction with the drawings. Show it:

FIG. 1

a spatial view of a device for the administration of liquids in the open state, wherein the springs, traction cables and bearings for the rocker arms are shown dissolved in the upper housing half state;

FIGS. 2a-f

FIG. 1 is a schematic sectional view of the apparatus of FIG. 1 showing the operation of the pressure application mechanism in a stepwise sequence; FIG. and

FIG. 3

a spatial representation of a charger for closing and opening the device shown in Figures 1 and 2.

As can be seen from FIG. 1, the illustrated one Device for the administration of fluids in which it in the present case, it is an infusion pump, an upper housing half 1 and a lower housing half 2, pivotable with each other via a hinge shown at 9 are connected. Both halves form in a closed Condition a case that is a flat, approximately rectangular Owns shape and a pressure buckle comes close. On the back of the lower half of the housing 2 are two Gurtlaschen arranged, through which a belt can be pulled, with which the infusion pump can be worn on the body.

When the upper case half 1 pivots to close is, are two laterally on the lower half of the housing. 2 arranged closure tabs 8 pressed slightly outward and slide in a corresponding area of the upper half of the housing 1 up, until finally in a corresponding Free space inside and thus both Lock housing halves tightly together. The housing halves can not be easily opened then, Rather, this is a later described special device needed.

Within the housing is a plunger 3, which has approximately rectangular shape and slightly downwards is formed concavely curved. The plunger 3 is via a rotation axis 13, which is arranged approximately centrally on the plunger is rotatably mounted on four rocker arms 5, 6, which in turn on the inside of the upper half of the housing 1 are slidably mounted and rotatable. How to figure 1 can take, extend the two inner rocker arms 5, 6 from the axis of rotation 13 in Figure 1 to the right, while the two outer rocker arms from the axis of rotation 13 extend in the figure to the left. There are thus approximately symmetrical conditions.

The sliding and rotatable mounting of the four rocker arms on the upper housing half is accomplished with rollers 4, each one roll on one side of a Rocker arm is arranged. These rollers 4 are in complementary recesses in inwardly projecting Portions of the inside of the upper half of the housing 1 stored. The rollers 4 have around their circumference middle grooves (not shown), which with corresponding Webs (not shown) on the inside of the upper Housing half 1 in contact. The rollers 4 can roll along these bars

The rocker arms 6 are flexible tension cables 5 with tension springs 10 in conjunction, the rocker arms in their on the Inside the upper half of the housing 1 arranged end portion (Rollers) apply a tensile force. The exact one Function of the springs and rocker arms is based Figure 2 explains.

FIGS. 2a-f show schematic sectional views through the device of Figure 1 to illustrate the operation the mechanism for pressure application in gradual Sequence. It is only one in the figures Rocker arm 6 is shown with a tension spring 10.

FIG. 2a shows the housing consisting of the two housing halves 1 and 2 in the closed state with filled infusion solution bag 15 inserted. It can be seen that the pressure piston 1 is pressed against the bag 15 with the downward force F ₂ , with the aid of the rocker arm 6, whose right end in the figure is rotatably mounted on the plunger 3. The left end in the figure of the rocker arm 6 is slidably mounted and rotatably mounted on 14 rotatably mounted rollers 4 on the inside of the upper half of the housing 1, as described above in connection with Figure 1. At this end of the rocker arm 6, a tension spring 10 engages via a flexible tension cable 5. The tension spring 10 has a length L and acts with a tensile force F ₁ , which is directed to the right in the figure, on the rocker arm. The height of the bag 15 is designated H.

It can be seen that the rocker arm 6 with the horizontal one Forms angles of 0 °, i. the rocker arm 6 takes its in the horizontal pivoted position in which the tension spring 10 is the longest. It also recognizes that the flexible traction cable 5 over the top of the rocker arm 6 is guided. This top is approximately roof-shaped formed so that the rocker arm 5 acts as an eccentric, and deflects the left end of the rocker arm 6 in the figure fixed rope 5 um. The distance between the contact point of the traction cable 5 with the top of the rocker arm on Plunger corresponds to the lever arm, over which the spring force acting on the plunger.

FIG. 2b shows the bag 15 in an already slightly emptied one Position. Here is the plunger 3 already moved down, and the rocker arm 6 takes a position of 7.5 ° to the horizontal, as indicated by the angle α. Further, in Figure 2b, the horizontal distance between the pivot points with h, the distance between Fulcrum of the rocker arm on the plunger 3 and the contact point of the pull rope 5 (lever arm) with e, the pulling direction of Spring with β and the length of the spring 1.

Figures 2c-2f show further stages in the operation of the mechanism, wherein Figure 2f the lowest position of the plunger 3 shows, in which the rocker arm 6 a Angle of 37.5 ° with the horizontal forms. In this Position, the tension spring is almost relaxed.

Figure 3 shows a device for opening and closing the in the Figures 1 and 2 shown apparatus. The device owns a frame-shaped lower part 20, which is an extendable Part 21 with a front handle 29 has. The cream-shaped lower part 20 forms a bearing for the openable or device to be closed, there between the two Long legs and the front transverse leg 22 and the rear transverse leg of the frame-shaped lower part 20th can be fixed.

The lower bearing part 20 is pivotable with an upper Part 23 connected, which is bow-shaped and also has an extendable part 24, at the front a handle 30 is arranged. With the help of Handles 29 and 30, the two parts 20 and 23 on a suitable length are brought. The bow-shaped top 23 is after inserting the device to be closed moved down, with one between the longitudinal legs the part 23 arranged transverse portion 25 which is rotatable is arranged against the top of the upper half of the housing the device is pressed. This way will the device is closed.

Between the longitudinal limbs of the upper part 23 is also an opening device 27, i. a device for releasing the locking of the at least one locking tab with provided the other housing part of the device. These Opening device 27 has a crossbar with a at 31 indicated pressing section on which by means of finger pressure the crossbeam is moved down. In the two lateral End portions of the crossbar are wedge-shaped sections 28 arranged at the downward movement of the the upper half of the housing of the device to be opened attacking Press locking tabs laterally outward, see above that the catch between two housing halves solved becomes. This snaps the upper half of the device something upwards and can thus be opened manually become. The device can then be removed from the charger to remove the used bag and to insert a new bag.

In other words, the lock (locking tab) is manually unsolvable, because of the very high spring pressure in the Inside the lock tab so hard into the notch on the housing top is pressed that the closure flap in existing Internal pressure only very difficult from the Rastpostion can be solved. The charger now serves, by means of the cross section 25 and the extendable lever 24 this Counteract internal pressure, so that the closure tabs the locking position are released and so with the opening device 27 the tabs without much effort on the page can be pushed.

Claims (11)

1. A device for administering liquids, especially infusion solutions, comprising
   a lower casing half (2),
   an upper casing half (1) connected with the lower casing half (2),
   a closure holding together the casing halfs (1, 2) in a closed condition for the formation of a casing and
   an application mechanism for a bag (15) laid between the lower casing half (2) and the mechanism and filled with the liquid to be administered, said application mechanism applying such a force to the laid in bag (15) when the casing is closed that a pressure is generated in the bag (15) which causes the discharge of a constant liquid volume per unit of time over the period of time of the
   administering process, wherein the mechanism comprises a rocking lever (6) applying a force to the bag (15) and variable in its angular position relative to the bag (15) by a tension spring (10),
   characterized in that
   the upper casing half (1) is pivotally connected with the lower casing half (2),
   the mechanism acts on a pressure piston (3) located in the casing, the bag (15) being located between the pressure piston and the lower casing half (2), wherein the tension spring (10) biasses the rocking lever (6) into its tilting position corresponding to the lowermost position of the pressure pistion, and
   the rocking lever (6) is pivotally and displaceably supported at the upper casing half (1) with one end and pivotally supports the pressure piston (3) with the other end.
2. The device according to claim 1, characterized in that the tension spring (10) acts upon the one end of the rocking lever (6) by means of a flexible cable (5).
3. The device according to claim 2, characterized in that the flexible cable (5) is guided over the upper side of the rocking lever (6) and that the upper side is formed in a predetermined contour, especially approximately in a roof-like manner, wherein the cable, dependent on the angle of position of the rocking lever (6), is turned round differently.
4. The device according to one of the preceding claims, characterized in that it comprises at least two rocking levers (6) acting oppositely with respect to one another and having associated oppositely acting tension springs (10), wherein the rocking levers (6) have a common pivot axis (13) at their respective other ends at the pressure piston (3).
5. The device according to claim 4, characterized in that it includes, with regard to the common pivot axis (13), two inwardly positioned rocking levers (6) acting in one direction from the common pivot axis (13) and two outwardly positioned rocking levers (6) acting in the opposite direction with corresponding tension springs (10).
6. The device according to one of the preceding claims, characterized in that the rocking levers (6) are adapted to be displaced on webs by means of rollers (4) wherein the rollers (4) in their end position are rotatably supported in complementary concave recesses of the upper casing half (1).
7. The device according to one of the preceding claims, characterized in that it includes a flat casing.
8. The device according to one of the preceding claims, cahracterized in that the casing and the pressure piston (3) are formed approximately rectangularly.
9. The device according to one of the preceding claims, characterized in that the pressure piston (3) is concavely formed downwardly in the direction of its longitudinal axis for the adaption to the bag (15) containing the the liquid which is to be administered.
10. The device according to one of the preceding claims, characterized in that the casing has at least one belt buckle on its backside.
11. The device according to one of the preceding claims, characterized in that the closure has at least one closing tongue (8) located at one casing half (1, 2), outwardly engaging the other casing half during closing and lockingly engaging the other casing half.

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